First, the jury is deciding the fate of a drug executive charged in a drug problem and meningitis. Reporter: The mold. The bacteria. Reporter: The prosecution says Barry Canton almost single handedly caused a public health crisis. On advice of council -- Reporter: He pleaded the fifth. When investigators went to his factory, it was a place of filth, rusted equipment. Turning out batches of tainted medicine that led to an epidemic of nexts, including Patricia. Still in pain five years later. I cry. I get angry. My physical life is much different. I don't have the energy that I used to. I feel extra pain. I have head pain. Reporter: Prosecutors say a total of 753 people across the country were stricken after taking the tapted medicine. 64 of them died. For the last three months, federal prosecutors in Boston have been presenting their evidence. Including videos of Canton telling his employees not to worry about state health inspectors. How can they come in and inspect me? They don't even know what they're looking at. They have no clue. Reporter: As part of his alleged scheme, Cadden made lists of patients, including Donald Trump, Calvin Klein, and Jennifer Lopez, to be kounlted as a manufacturer. That's something for another time. Yeah. Let no -- we can talk about that. That's actually one of the more difficult things we do. Let's just talk about the products now. Okay, that's fine. Or we'll be in court. Reporter: Mr. Cadden, what would you like to say? Reporter: He admitted something wept wrong. Brian Ross, ABC news, New York. We want to thank Brian Ross for his reporting. Two things putting a smile on my face. One of them, Sam champion. The other, spring is tomorrow.

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